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1.
The replicative abilities and tissue tropism properties of 13 non-pathogenic or low-pathogenic waterfowl-origin type A influenza isolates recovered in 1986 were examined in chickens. Following intravenous challenge, reisolation of challenge virus was attempted from swabs of the luminal surfaces of the cloaca, jejunum, ileum, bursa, trachea, and air sacs and from swabs of bone marrow and liver tissues. Virus-isolation attempts were also accomplished on brain, thymus, spleen, pancreas, gonad, kidney, blood, and lung tissues. The overall frequency of influenza virus recovery for each experiment ranged from 3.1% to 49.3%. For all experiments combined, 58.3% of the kidney tissues and 62.9% of the cloacal swab samples collected on days 1 to 10 postinoculation were positive for challenge virus recovery. Virus titers up to 10(8.7) mean embryo infective dose per gram of kidney tissue were demonstrated in clinically normal chickens. Distinct biological variations and nephrotropism appear to exist among the corporate properties of virus populations making up each of the 13 waterfowl-origin type A influenza isolates. 相似文献
2.
Specific-pathogen-free chickens were infected via the trachea when 4 weeks old with 2000 plaque-forming units (PFU) of the virulent Australian infectious laryngotracheitis (ILT) virus strain CSW-1. Titers of ILT virus in the trachea were greatest (10(7.0) PFU/ml in washings, 10(6.0) PFU/g of tissue) 2-4 days postinfection (PI). Infectivity then declined rapidly, to become undetectable by 7 days PI, although highly localized areas of ILT antigen in the tracheal epithelium were occasionally observed by fluorescent antibody staining at 7 and 8 days PI. Tracheal organ cultures established 7 and 8 days PI provided no evidence of latent ILT virus infection at this immediate post-acute stage of pathogenesis. ILT virus was not isolated from peripheral blood leukocytes or lymphoid organs (spleen, bursa, thymus). ILT virus was found in the trigeminal ganglia and/or brain in 14 of 36 chickens (40%) examined between 4 and 7 days after intratracheal inoculation, but it was not in these tissues in five chickens examined at 8 days PI. Virus was also detected at 6 days PI in the trigeminal ganglia in one of five chickens infected by the conjunctival route. These data indicate that the early pathogenesis of ILT (CSW-1) infection frequently involves the tissues of the nervous system. In acute ILT in 4-week-old chickens, interferon-alpha/beta activity was not detectable in serum or tracheal exudates within 14 days PI, but tracheal washings contained significant virus-neutralizing activity by 7 and 8 days PI. In 3-day-old chickens infected via the trachea with 200 PFU of ILT CSW-1, the clearance of ILT virus from the trachea was similar to that observed in 4-week-old chickens, but ILT virus spread systemically to the livers of 20% by 5-7 days PI. 相似文献
3.
呼吸型鸡传染性支气管炎病毒的抗原定位与动态分布 总被引：1，自引：0，他引：1
应用间接免疫荧光抗体(IFA)和RT-PCR法对人工感染IBV-M41株的SPF鸡不同脏器中的病毒进行了跟踪检测。结果在感染后24h气管中最早出现特异性荧光，感染后第3h肺脏和肾脏出现特异性荧光，感染后第5d肝脏、脾脏、法氏囊、直肠等脏器也不同程度的出现特异性荧光，特异性荧光在气管中最强，持续时间也最长，可达14d或更长：在肺脏和肾脏可持续3～5d；而在其他器官持续1～3d。试验结果表明气管、肺脏、肾脏都是M41株病毒增殖的场所，但随感染时间的延长，病毒最终定位于主要的靶器官气管。IFA和RT-PCR方法均可以对IBV抗原定位，相对来说IFA法更直观，而RT-PCR更灵敏。 相似文献
4.
Takami S Goryo M Masegi T Okada K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(1):13-18
The major organs and tissues of 24 broiler chickens (70 or 71 days old) suspected of spindle-cell proliferative disease (SPD) because of showing the tumorous lesions distributed throughout the body at meat inspection were collected for histopathological and immunohistochemical examination. Macroscopically, liver, spleen and cecal tonsil showed severe enlargement and white nodules or plaques were observed in the liver, spleen, kidney, intestine and bone marrow of the femur. All chickens were diagnosed with SPD based on the histopathological examination. The lesions of SPD were observed in the liver, spleen, kidney, heart, lung, pancreas, proventriculus, gizzard, duodenum, jejunum, ileum, rectum, cecal tonsil, bursa of Fabricius, bone marrow of the femur and skin. Hemangioma was observed in the lung of 1 bird. Eight 1-day-old specific pathogen-free chicks were inoculated intraperitoneally with 0.25 ml of a 20% homogenate of the affected spleens of three naturally occurring cases. One inoculated bird, necropsied at 10 weeks of age, macroscopically had a white nodule in the kidney and histopathologically had spindle-cell proliferative lesions, a pattern similar to that seen in the naturally occurring cases, in the liver, spleen, kidney, heart, lung, pancreas, proventriculus, duodenum, cecal tonsil and bone marrow of the femur, and was diagnosed with SPD. Immunohistochemically, significant positive reactions with a rabbit antiserum against avian leukosis virus antigens were detected in all spindle cells in the proliferative lesions of all examined SPD cases and in tumor cells of the hemangioma of a field case. 相似文献
5.
鸡感染传染性支气管炎病毒后脏器内病毒动态分布研究 总被引：1，自引：1，他引：0
对IBV在鸡器官内动态分布进行了初步研究。分别用IBV T株、M41、H52、H120、上海野毒(Sh1、Sh2、Sh3)对7个试验组的鸡攻毒,分别用AIV、NDV以及IBDV对3个对照组鸡攻毒,然后定期剖杀采样,并用套式RT-PCR方法进行检测。结果为攻毒后第3天和第7天,7个IBV攻毒组的肾脏、气管、肝脏、肺脏和扁桃体中均检测到IBV;第14天,H52组、H120组肝脏、扁桃体IBV检测阴性,其余脏器均为阳性,其他组5个脏器均为阳性;第21天,M41组、H52组、H120组肾脏、肝脏、扁桃体检测阴性,其余为阳性,其他组5个脏器全为阳性;第28天,M41组、T组、H52组、H120组、Sh1组肾脏、肝脏、扁桃体以及T组的肝脏和扁桃体为阴性,其余脏器为阳性,其他组5个脏器仍为阳性;35 d后,各实验组各脏器均为阴性。整个试验阶段,对照组的IBV检测均为阴性。由此可见,IBV不同毒株组织嗜性存在明显差异,导致IBV各毒株在感染鸡体内的分布和消长规律存在着差异。这为阐明IBV致病机理提供了必要的试验依据。 相似文献
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7.
雏鸡感染马立克氏病病毒后免疫器官组织抗体生成细胞的变化 总被引：2，自引：0，他引：2
以马立克氏病病毒（ＭＤＶ）感染１日龄肉用雏鸡，在感染后５、２５、４５ｄ采取法氏囊、脾脏、盲肠扁桃体和哈德尔腺，用彩色免疫金银染色法检查免疫器官组织中ＩｇＧ、ＩｇＭ和ＩｇＡ抗体生成细胞数量的动态变化。结果：ＭＤＶ感染雏鸡的法氏囊、脾脏和哈德尔腺中以ＩｇＧ抗体生成细胞居多，ＩｇＧ、ＩｇＭ和ＩｇＡ抗体生成细胞均较正常对照鸡显著减少；盲肠扁桃体中以ＩｇＡ抗体生成细胞居多，ＩｇＡ、ＩｇＧ和ＩｇＭ抗体生成细胞数量显著低于正常对照鸡。由此表明，ＭＤＶ感染鸡全身免疫器官和消化道、呼吸道局部粘膜体液免疫机能明显抑制。 相似文献
8.
Chang-Won Lee Corrie Brown Mark W Jackwood 《Journal of veterinary diagnostic investigation》2002,14(5):377-381
Chicken embryos were inoculated with 8 different strains of infectious bronchitis virus (IBV) representing 7 different serotypes at 17 days of embryonation. At 2 and 5 days postinfection (dpi), tissues were collected for in situ hybridization using an antisense digoxigenin-labeled riboprobe corresponding to the sequence of the mRNA coding for the membrane protein. Extensive antigen staining in the cytoplasm of epithelial cells in the trachea, lung, bursa, and intestine was detected at 2 dpi with all 8 strains of IBV. At 5 dpi, little or no positive staining was observed in these tissues. However, tubular cells of the kidney showed multifocal positive staining with the Wolgemuth strain-, Gray strain-, JMK strain-, and Mass41 strain-infected chickens. No viral RNA was detected in the spleen at any time point. The results demonstrated strict epitheliotropic nature and wide tissue tropism of strains of IBV in the chicken embryo and the universality of our riboprobe. In situ hybridization with this probe will be useful for understanding the tissue tropism and the pathogenesis of IBV in vivo. 相似文献
9.
Replication of a waterfowl-origin influenza virus in the kidney and intestine of chickens 总被引：1，自引：0，他引：1
Intravenous inoculation of chickens with a waterfowl-origin type A influenza virus resulted in high titers of virus in kidney tissues and viral nucleoprotein in renal tubular epithelial cells and in intestinal mucosal epithelial cells. Virus titers in kidneys of four of eight clinically normal chickens sampled on days 3 and 5 postinoculation (PI), one dead chicken on day 3 PI, and one dead chicken on day 7 PI exceeded 10(6) mean embryo infectious dose per gram of tissue. Using immunofluorescent and immunoperoxidase staining, viral nucleoprotein was identified in the cytoplasm and nucleus of tubular epithelial cells in kidneys and in nucleus of mucosal epithelial cells lining villi in the lower small intestine. Based on the low intravenous pathogenicity index for this virus (0.3) along with the high virus titers in kidney tissues and localization of viral antigen in kidney important site for replication of avian influenza (AI) virus of low pathogenicity. Recovery of type A influenza viruses from cloacal swabs could result from viral replication in kidneys as well as in the lower intestine and/or the bursa of Fabricius. 相似文献
10.
11.
Tissue tropism properties of A/chicken/Alabama/75 (H4N8) were examined after intravenous inoculation of 5-week-old specific-pathogen-free chickens. From 14 clinically normal chickens euthanatized on days 1-20 postinoculation, the frequencies of virus recovery were highest for cloacal swabs (86%), bursal swabs (64%), and kidney tissues (64%) and lowest for tracheal swabs (14%), thymus tissues (14%), bone-marrow swabs (7%), and brain tissues (0%). Evidence that the high frequency of virus recovery from kidney tissues was associated with virus replication in the kidney tissues was provided by high virus titers, ranging up to 10(9.5) mean embryo infectious dose per gram of kidney tissue, and by identification of intranuclear and intracytoplasmic type A influenza nucleoprotein in kidney cells using immunohistochemistry. Virus-recovery and virus titer results from three chickens that died on days 4 and 5 postinoculation paralleled the results from the clinically normal chickens. These findings indicate that A/chicken/Alabama/75 has nephrotropic properties similar to nephrotropic properties previously reported for waterfowl-origin type A influenza viruses and provide evidence that kidney lesions could be manifestations of systemic influenza infections in commercial laying chickens. 相似文献
12.
Egyptian geese (Alopochen aegypticus), a duck species endemic to sub-Saharan Africa and occasionally implicated in the transmission of avian influenza viruses (AIV) to farmed ostriches, were experimentally infected with low pathogenicity H7N1 and H6N8 viruses to assess viral shedding and immune profiles. Following the first infection with H7N1 virus, high titers of virus were shed from both the tracheae and cloacae for at least 7 days postinfection, and tracheal shedding lasting until day 14. All detectable shedding from both tracheae and cloacae had ceased within 28 days of infection. Antibody titers peaked at day 7 postinfection, but the initial immune response was short-lived. Birds that received a second challenge with the homologous H7N1 virus mounted a more robust response that lasted beyond 66 days postchallenge, and H7N1 virus was detected, albeit at much lower levels, until day 28 post secondary infection (psi) in the cloaca and beyond day 28 psi in the trachea. Birds that received an initial infection with H7N1 virus were also challenged with H6N8 virus, and because a comparable shedding pattern to the H7N1 challenge group was observed, we concluded that the effect of any nonspecific immunity was negligible. 相似文献
13.
本试验旨在探讨高致病性猪繁殖与呼吸综合征病毒(HP-PRRSV)对地方品种猪的致病特点。将HP-PRRSV经滴鼻感染4月龄健康莱芜黑猪,观察接毒后的表现,于接毒不同时期颈静脉采血,ELISA试剂盒(IDEXX)检测外周血血清抗体水平的动态变化,定期剖杀,采集相关的器官组织制备组织切片,HE染色,观察不同组织的动态病理学变化,免疫组化染色检测病原在不同组织中的分布。结果表明,攻毒后第2天便出现一定的临床症状,但持续2d后症状就基本消失,感染猪未见死亡。攻毒后5d便可检测到抗体阳性(1/7),14d抗体达峰值。攻毒后3d便可见间质性肺炎,轻微的病毒性脑炎,实质器官颗粒变性;攻毒后7d出现典型的间质性肺炎、淋巴组织坏死、各段肠管大量嗜酸性粒细胞浸润及实质器官出现空泡变性。在攻毒后2～4周内,肺一直表现典型的间质性肺炎,病毒性脑炎逐渐加重,肾上腺变性坏死,胰腺轻微的炎性细胞浸润,甲状腺轻微充血、出血,实质器官出现严重的空泡变性。PRRSV抗原阳性信号出现在淋巴组织(淋巴结、脾、扁桃体)、气管、心、肝、肺、肾、胃、十二指肠、空肠、回肠、甲状腺、肾上腺、颌下腺、子宫、大脑及小脑内;盲肠、结肠、直肠、膀胱、胰腺、输卵管及卵巢均未见到阳性信号。阳性信号主要位于感染细胞的胞质中,偶尔出现在核内。试验结果表明:HP-PRRSV人工感染4月龄莱芜黑猪具有广泛的组织嗜性,并导致广泛的组织损伤,但临床症状表现轻微,未见死亡现象,4月龄莱芜黑猪对HP-PRRSV感染具有较强的抵抗力。试验结果为进一步研究HP-PRRSV对我国地方猪与外源品种猪的致病性差异提供了一定的理论依据。 相似文献
14.
In situ hybridization and immunohistochemistry were utilized to identify tissues infected in ovo with infectious bronchitis virus (IBV). Chicken embryos were inoculated in ovo (chorioallantoic sac) with the Arkansas (Ark) serotype of IBV at 18 days of age. At 24, 48, 72, and 120 hr postinfection (HPI), bursa, lung, spleen, heart, and thymus were collected, fixed in 10% neutral buffered formalin, and paraffin embedded. The digoxigenin-labeled antisense S1 riboprobe detected viral mRNA in the cytoplasm of respiratory epithelial cells in the primary bronchus at 24, 48, and 72 HPI. Viral mRNA was detected in bursa samples collected at 48 hr. Immunohistochemistry detected viral antigens in epithelial cells of the parabronchi and bursal tissues at 24 and 48 hr, respectively. No viral mRNA or antigen was detected by in situ hybridization or immunohistochemistry, respectively, in heart, thymus, or spleen at any time after inoculation. On the basis of these data, IBV apparently initially infects lung tissue, then migrates to and infects cells of the bursa. These results indicate that in situ hybridization can be useful in detection of IBV-infected chickens and in understanding the pathogenesis and virulence of IBV infection. 相似文献
15.
Establishment of persistent avian infectious bronchitis virus infection in antibody-free and antibody-positive chickens 总被引：2，自引：0，他引：2
Avian infectious bronchitis virus (IBV) causes a highly contagious and economically significant disease in chickens. Establishment of a carrier state in IBV infection and the potential for the persistent virus to undergo mutations and recombination in chicken tissues have important consequences for disease management. Nevertheless, whether chickens can maintain persistent IBV infection in the absence of reinfection from exogenous sources or the presence of antibody in the host can modulate virus persistence remains unclear. Indeed, whether or not IBV genome can undergo genetic changes during in vivo infection has not been demonstrated experimentally. In the present study, IBV shedding and tissue persistence were monitored in individual chickens maintained under strict isolation that precluded reinfection from exogenous sources. In the first of two experiments, intranasal exposure of 6-wk-old antibody-free chickens to IBV vaccine virus resulted in intermittent shedding of the virus from both trachea and cloaca of individual birds for up to 63 days. Also, the virus was recovered from the internal organs (spleen, gonad, kidney, lung, cecal tonsil, and cloacal bursa) of six of eight birds killed at various intervals between 27 and 163 days postinoculation (DPI). In the second experiment, IBV exposure of 1-day-old maternal antibody-positive chicks led to periodic virus shedding from the trachea and cloaca in all chickens until 77 days; however, internal organs (lungs and kidneys) of only one of seven birds (killed at 175 DPI) were virus positive, suggesting that presence of antibody at the time of infection protects internal organs from IBV infection. When the lung and kidney isolates of IBV from the latter experiment were compared with the parent-vaccine virus, no changes in their antigenicity, tissue tropism, or the nucleotide sequence of the S1 glycoprotein gene were observed. These findings indicate that, unlike the mammalian coronaviruses, propensity for frequent genetic change may not be inherent in the IBV genome. 相似文献
16.
为检测aBD-1mRNA在佳米驴体内可能的表达器官,根据已知aBD-1cDNA的全长序列设计一对预计扩增产物为266bp的引物,以佳米驴舌背表面、食管、胃、十二指肠、空肠、回肠、盲肠、结肠、直肠、气管、胰腺、膀胱、子宫、心脏、肝脏、肺脏、肾脏、脾脏、淋巴结、卵巢组织中提取的总RNA为模板,采用反转录PCR（RT—PCR）技术检测佳米驴的上述器官内aBD-1mRNA的表达情况,同时以β-肌动蛋白（β-actin）基因作为内参。结果显示：aBD-1mRNA在佳米驴的舌、盲肠和结肠内有强的表达,在食管、胃、十二指肠、空肠、回肠、直肠、气管内有比较强的表达,在膀胱和子宫内有弱的表达,而在心脏、肝脏、脾脏、肺脏、肾脏、胰腺、淋巴结、卵巢等实质性器官组织内无表达。 相似文献
17.
Localization of astrovirus in experimentally infected turkeys as determined by in situ hybridization
Behling-Kelly E Schultz-Cherry S Koci M Kelley L Larsen D Brown C 《Veterinary pathology》2002,39(5):595-598
Twenty-one 3-day-old turkey poults from British United Turkeys of America were orally inoculated with a recently characterized astrovirus, TAstV-2, isolated from turkeys with poult enteritis and mortality syndrome. At 1, 2, 3, 4, 5, 7, and 9 days postinfection (dpi), three inoculated birds were euthanatized, and tissues (intestines, spleen, bursa, and thymus) were collected immediately into 10% neutral buffered formalin. Inoculated birds were diarrheic by 3 dpi, and frothy feces persisted throughout the experimental period. Histologically, there was only slight evidence of enteric damage, which was characterized by mild epithelial necrosis, lamina propria infiltrates, minimal villus atrophy, and mild crypt hyperplasia. In situ hybridization, using a negative sense digoxigenin-labeled riboprobe to the capsid gene of TAstV-2, revealed viral RNA in intestinal epithelial cells at the basal margins of the villi, in distal small intestine, and in cecum at 2 dpi, with subsequent extension to epithelium of the large intestine and proximal small intestine (3-5 dpi). Minimal virus remained by 9 dpi. 相似文献
18.
J E Heidrich M A Adcock C Bolin N F Cheville R E Smith 《Veterinary immunology and immunopathology》1987,15(3):267-283
Infection of chicks or chick embryos with Rous associated virus number 7 (RAV-7) led to a decreased blastogenic response to Concanavalin A (Con A) by lymphocytes isolated from the spleen and thymus. Chicks infected with RAV-7 8 days after hatch manifested decreased Con A blastogenesis 5 weeks postinfection, while chicks infected in ovo at 10 days of incubation showed an unusual pattern of cell density dependent decreased blastogenesis two weeks post-hatch (three weeks post-infection). Histopathological examination of tissues from RAV-7 infected chicks revealed evidence of lymphoid organ involution and widespread lymphoproliferative lesions by 3 weeks of age. The combination of decreased in vitro lymphoid blastogenesis and in vivo lymphoproliferation suggests that RAV-7 interacts with lymphocytes in a fashion that has not previously been described in the chicken. 相似文献
19.
Control of infectious bursal disease virus (IBDV) by vaccination is important for poultry production worldwide. Two vaccines, an IBDV immune complex (ICX) vaccine and an IBDV-2512 vaccine, were administered at 100 mean embryo infectious dose to specific-pathogen-free 18-day-old broiler embryos in ovo. At 3, 6, 9, 15, and 21 days post in ovo vaccination (PIOV), bursa, spleen, and thymus tissues were collected and analyzed for virus protein by antigen capture chemiluminescent enzyme-linked immunosorbent assay (ELISA). Chicks were bled and antibody titers were determined by the antibody ELISA. At 21 days PIOV, chickens were challenged with a 1:500 dilution of an antigenic standard IBDV strain. At 28 days PIOV, birds were euthanatized and bursa weight:body weight ratios were determined. Embryos vaccinated with either vaccine exhibited 92% hatchability; however, within 1 wk of hatch, birds vaccinated with IBDV-2512 showed 56% mortality, whereas those given IBDV-ICX had only 3.2% mortality. Both IBDV-ICX and IBDV-2512 vaccines were detected in bursa, spleen, and thymus at day 3 PIOV. A 5-day delay in virus replication was observed with IBDV-ICX vaccine. By day 15 PIOV, the IBDV-ICX was no longer detectable in the bursa and spleen but persisted in the thymus. The IBDV-2512 vaccine persisted in the spleen and thymus on day 15 PIOV. By day 21 PIOV, neither vaccine virus was detected in any lymphoid organ. This assay can be useful in the early detection of vaccine virus in the tissues of chickens vaccinated via the in ovo route. Both vaccines caused bursal atrophy at all times PIOV. The IBDV-2512 caused splenomegaly at day 6 PIOV, whereas splenomegaly was not seen in IBDV-ICX-vaccinated birds until day 9 PIOV. Thymus atrophy was observed in IBDV-2512-vaccinated chicks from day 3 PIOV, whereas this occurred on day 15 PIOV in IBDV-ICX-vaccinated birds. Bursa weight: body weight ratios in IBDV-ICX-vaccinated unchallenged and vaccinated challenged birds were not different (P < 0.05). 相似文献
20.
R A Heckert L J Saif G W Myers A G Agnes 《American journal of veterinary research》1991,52(6):845-851
Blood, feces, and nasal swabs specimens were collected 12 to 24 hours after birth and then 3 times/week (blood only once per week) from one group of 10 calves until they were 10 weeks old and from a second group of 10 calves until they were 10 to 20 weeks old. Colostrum was collected from all calves' dams and tears from 5 randomly selected calves in the first group. All fecal and nasal specimens were assayed for bovine coronavirus (BCV) antigens by ELISA. Nasal epithelial cells were examined for BCV antigens by direct immunofluorescence. Isotype antibody titers to BCV in all samples from 5 calves in group 1 were evaluated by ELISA. Zinc sulfate turbidity (ZST) values were determined on the first serum samples taken from all calves in group 1. To determine whether any correlation existed between ZST values, isotype antibody titers to BCV (12 to 24 hours after birth), number of respiratory sick days, number of enteric sick days, or days to first shedding of virus, a Spearman rank order correlation coefficient was done. Bovine coronavirus respiratory tract and enteric tract infections were common on this farm. Most initial infections developed when calves were 1 to 3 weeks old; however, there were also multiple incidences of shedding of viral antigens or seroconversions at later times during the study. Persistence of infection or reinfection of the upper respiratory tract with BCV was common. Colostral antibody titers to BCV (IgG1) were in all cows at moderate amounts; however, calf serum antibody titers and ZST values (12 to 24 hours after birth) were highly variable.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献